/*
 * Copyright (c) 2012, Fredrik Yttergren
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name LucidBot nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL Fredrik Yttergren BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package internal.irc.delays;

import api.runtime.ThreadingManager;

import javax.inject.Inject;
import java.nio.charset.Charset;
import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

class BufferDelayHandler implements DelayHandler {
    private static final int MAX_BUFFER_SIZE = 9;
    private static final int DELAY = 1000;
    private static final int SECOND_ADD_INTERVAL = 90;

    private final AtomicInteger bufferSize = new AtomicInteger(0);

    @Inject
    BufferDelayHandler(final ThreadingManager threadingManager) {
        threadingManager.scheduleRecurring(new Runnable() {
            @Override
            public void run() {
                if (bufferSize.get() > 0) bufferSize.decrementAndGet();
            }
        }, DELAY, DELAY, TimeUnit.MILLISECONDS);
    }

    @Override
    public <E> E callWithDelay(final String line, final Callable<E> callable) throws Exception {
        int bytes = line.getBytes(Charset.forName("UTF-8")).length;
        int secondsFromLength = bytes / SECOND_ADD_INTERVAL + 1;
        while (bufferSize.get() + secondsFromLength > MAX_BUFFER_SIZE) {
            Thread.sleep(DELAY);
        }
        bufferSize.addAndGet(secondsFromLength);
        return callable.call();
    }
}
